Method of manufacturing bolts.



E- l. DODDS.

METHOD OF MANUFACTURING BOLTS. APPLICATION FILED MAY 11. 19H.

Patented Nov. 7, 1916.

an sas ATNT reins.

ETHAN I. DODDS, OF CENTRAL VALLEY, NEW YORK, AS$IGNOR TO KEBFTER MANUFAC- TURING COMEANY, OF PITTSBURGH, PENNSYLVANIA, I; CORFORATION OF PENET- SYLVANIA.

METHOD OF MANUFACTURING BOLTS.

Specification of Letters Patent.

Patented Nov. Z, 191' To all whom it may concern:

Be it known that I, ETHAN I. Donne, a citizen of the United States, residing at Central Valley, Orange county, New York, have invented a new and. useful Method of Manufacturing Bolts, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is a sectional perspective view, largely conventional, showing one form of heating furnace which I may use in carrying out my invention; Fig. 2 is a perspective view, also largely conventional, showing one form of upsetting and welding dies; Fig. 3 is an elevation, partly in section, and illustrating the manner in which the stay bolts are twisted; and Figs. 4 and 5 are elevations showing apparatus for threading the bolts. Figs. 3, 4 and 5 are also largely conventional. Fig. 6 is a plan View of a track bolt made in accordance with my invention.

My invention has relation to a novel method of making stay bolts and the like of the general character described and claimed in Patent No. 1,121,173, December 15, 1914, and also track bolts and the like of the general form described and claimed in my pendapplication Serial No. 7 59,916, filed April 9th, 1918. The stay bolts consists of solid threaded end heads, which are connected by two bar members, which are twisted upon each other through an angle of at least 180 degrees. The track bolts consist of a body portion composed of a plurality of separable bar members twisted upon each other to an angle less than 180 degrees, and upset and welded at one end to form a flanged head, and welded and threaded at the opposite end.

In making my improved stay-bolts, I

preferably proceed as follows: I take two bar members preferably of stay bolt iron and pile them together to form a cylindrical blank. These blanks are then inserted in a suita le furnace, and are locally heated to approximately a sweating heat, at which the end portions of the bar members will begin to unite. The furnace should be of such character that only the end portions of the members which are to be upset to form the head of the bolt will be heated while the remainder of the blank is protected from being heated. In Fig. 1 I have shown, more or less conventionally, a suitable furnace for this purpose. his furnace, which is a gasfired furnace, is indicated at 8. r designates the opening through which the gas is delivered to the heating chamber of the furnace, and is the outlet opening leading to a stack, not shown. The heating chamber of the furnace is provided with a stepped wall 6, and the opposite wall is provided with a plurality of small openings 8 through which the blanks to be heated are inserted. The distance between the face of the stepped wall and the opposite wall is just sufficient to expose within the furnace the desired length of the blanks to be heated, while the rest of the length of the blanks being either in the wall or outside the furnace wall, and as the openings are only slightly larger than the blanks,

the portions of the blank which are not exposed to the gases in the furnace do not become heated to objectionable extent. After heating, the piled blank is withdrawn from the furnace and its heated end is simultaneously upset and welded by the action of suitable dies. Fig. 2 shows more or less conventionally dies which may be used for this purpose. In this figure, 9 designates a sectional die block between which the heated ends of the blanks are clamped, and which are formed with die cavities into which the said ends extend. By the action of a suitable plunger, such as shown at 11, the upsetting or welding to form the heads 12 is effected. The die cavities 10 should be larger than the diameter of the head desired, preferably by at least one-sixteenth of an inch, in order to compensate for the losses in scale when welding together a plurality of separate bar members, and also for losses by subsequent machining before threading. After forming one or both of the heads 12 in the manner described, the blank is then twisted through an angle of at least 90 degrees. I prefer that this twisting shall take p.ace after one end of the blank has been formed into a head and before welding and upsetting the other end; although this particular feature is not a part of my invention, being the invention of Henry Frauenheim, as claimed and described in his copending application filed May 17, 1913, Se rial lo. 768,286. This twisting may be effected by any suitable means.

In Fig. 3 l have shown the headed end of the blank as held in suitable clamp 13, while heads are the same as though the bolt had been continuously threaded from one end to the other and the intermediate portion of he bar then turned off to removethe threads of such portion. This threading may be eifected by first advancing one of the heads 12 while in a suitable lathe into a suitable threading die 15, as shown in Fig. l. After this headhas been threaded, the blank is reversed end for end, and the opposite end portion is then threaded in the same or a similar die, as indicated in Fig. 5. The usual telltale holes, not shown, may then be drilled longitudinally through one or both neads into each connecting bar member.

i-iy invention provides for the rapid, economical and efficient method of manufactur 111g bolts of this general character, whereby the original scaled or rolled surfaces of the portions ofthe bolts between the heads are undis urbed. This gives a much better sur.-

face for resisting the action of water than where a machined surface is exposed. Furthermore, by using two bar members, they will remain together in pile form during heating, whereas, it would be difficult to ing and WllllG inserting them intothe upsetting and .welding device.

By the term stay 'bolt as used herein,

and in the claims, I do not intend to restrict the use of my invention to bolts for boilers, as it is obviously adapted to'themanufacture of various bolts of this general type.

hold a'lar er' number to ether while heat inc method of manufacturing headed bolts, such as shown in Fig. 6, is similar to that above described, and only one end of the blank is upset, viz, the end which forms the flanged head 16. The other endsof the members are simply welded and threaded. The twisting of this form of bolts is ap proximately 90 degrees because it is' desired that the bolts shall not be rigid under tension stresses but shall be capable of some elongation under excess strains.

I claim 1. The herein describedmethod of manufacturing bolts and the like havingintegral heads and separate body portions extending from head to head, which consists in assembling a plurality of bar members to form a blank, heating a predetermined portion of the end of. the blank and protecting'the remainder of the blank from being heated, simultaneously upsetting and welding the heated end portion to form a head, and then twisting" the two separate members uponeach other, substantially as describec. i 2. The herein described method of manufacturing bolts and the like having integral heads and separate body portionsextending from head to head, which consists'iniassenr bling a plurality of bar members'toform a blanlg'heating a predetermined portion of he end of the blank and protecting the remainder of the blank from being'heated, simultaneously upsetting and welding the end portion to form head, thenheating a predetermined portion of the other end of the blank and protectingthe body portion 7 from being heated, and then simultaneously upsetting and welding said end portion to form the second head and twisting the body members about described, r

In testimony whereof, I have hereunto set myhand.

V V -ETHAN I. DoDDs,

Witnesses: V i

Gno. B. Breanne, Jnssn B. HELLER.

85, each other, substantially as Copies of this patent may be obtained for five cents each, by addressing the Commissioner of lateiits,

Washington, 116. 1 

